Menu
Forums
New posts
Search forums
What's new
New posts
New media
New media comments
New profile posts
Latest activity
Media
New media
New comments
Search media
Members
Current visitors
New profile posts
Search profile posts
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Forums
Cattle Boards
Health & Nutrition
Fetal Protection Vaccines (MLV) - Lucky_P
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Help Support CattleToday:
Message
<blockquote data-quote="Lucky_P" data-source="post: 1058019" data-attributes="member: 12607"><p>Ron, </p><p>They're non-cytopathic, but attenuated. </p><p>I'm 30+ years removed from my undergraduate training in microbiology/virology, so can't speak with any authority on how they're 'modified', these days.</p><p>In the past, researchers attenuated some viruses by 'running them through' non-target' species, or growing them in non-target origin cell lines - for example (and I'm just making these scenarios up out of thin air), maybe infecting goats with IBR and re-isolating the virus from the goat or growing BVD virus in baby hamster kidney cell line, etc. For some viruses, growing in an unnatural host lessens virulence. </p><p>Or, it may be that the vaccine strains were 'discovered' contaminating certain cell lines, and had lost their virulence after multiple passages in cell culture, or were just innately, a less virulent strain from the outset. </p><p></p><p>It's close to irrefutable that the mlvs elicit a stronger response in most animals, but the inactivated viral vaccines have come a long way over the past 20 years or so. And, in the hands of folks who may not really know what they're doing, or why...the inactivated products may be best, or at least, may do the least harm.</p></blockquote><p></p>
[QUOTE="Lucky_P, post: 1058019, member: 12607"] Ron, They're non-cytopathic, but attenuated. I'm 30+ years removed from my undergraduate training in microbiology/virology, so can't speak with any authority on how they're 'modified', these days. In the past, researchers attenuated some viruses by 'running them through' non-target' species, or growing them in non-target origin cell lines - for example (and I'm just making these scenarios up out of thin air), maybe infecting goats with IBR and re-isolating the virus from the goat or growing BVD virus in baby hamster kidney cell line, etc. For some viruses, growing in an unnatural host lessens virulence. Or, it may be that the vaccine strains were 'discovered' contaminating certain cell lines, and had lost their virulence after multiple passages in cell culture, or were just innately, a less virulent strain from the outset. It's close to irrefutable that the mlvs elicit a stronger response in most animals, but the inactivated viral vaccines have come a long way over the past 20 years or so. And, in the hands of folks who may not really know what they're doing, or why...the inactivated products may be best, or at least, may do the least harm. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Cattle Boards
Health & Nutrition
Fetal Protection Vaccines (MLV) - Lucky_P
Top